Cardinal Round Ring Reference Binder, 1-Inch, Black, Pack of 8 (00317-C) PVC-free poly material will not stick to materials stored inside -archival safe for all documents including photos Back-mounted round ring metal allows sheets to lay flat and provide a clean, professional spine Dual opening and closing triggers Horizontal pockets on inside front and back covers Cover board made from 100% recycled fiber with at least 98% post-consumer fiber